Phenyl Phosphorodi l-imidazolate

Physical Data an exceedingly hygroscopic white solid, mp 96-97 °C (mp 90-92 °C also reported ). 

Solubility sol acetonitrile, dioxane, THF relatively insol benzene, ether. 

Preparative Methods this reagent was first prepared in 81 % yield by reaction of 4 equiv of imidazole with 1 equiv of phenyl phosphorodichloridate in benzene at 60 °C5 The use of 2 equiv of imidazole and 2 equiv of triethylamine as base has been reported to give a yield of 98% of (1) (eq 1).  

Purification recrystallization from benzene, filtration under a water-free atmosphere, and drying under vacuum. 

Handling, Storage, and Precautions owing to its hygroscopic nature, exclusion of moisture in handling and use is essential should be stored in a sealed tube at —20 °C.  

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